Bit rude perhaps not to clarify, since you are still a PoW believer:

PoW gives you no defensive advantage whatshowever. This is why it is usefull in Bitcoin, because no participant should have any structural advantage; but when it comes to protecting my stuff, i do want asymmetry, and as much of it that i can possibly get.

The best example of asymmetrical defensive advantage: cryptographic keypairs.

Hope this helps